Every vow, and every binding oath to {h} afflict the soul, her husband may establish it, or her husband may make it void.

(h) To mortify herself by abstinence or other bodily exercise.

Wesley's Notes

30:13 To afflict her soul - Herself by fasting, by watching, or the like. And these words are added to shew that the husband had this power not only in those vows which concerned himself or his estate, but also in those which might seem only to concern her own person, or body, and the reason is, because the wife's person or body being the husband's right; she might not do any thing to the injury of her body without his consent.

Matthew Henry's Concise Commentary

30:3-16 Two cases of vows are determined. The case of a daughter in her father's house. When her vow comes to his knowledge, it is in his power either to confirm it or do it away. The law is plain in the case of a wife. If her husband allows her vow, though only by silence, it stands. If he disallows it, her obligation to her husband takes place of it; for to him she ought to be in subjection, as unto the Lord. The Divine law consults the good order of families. It is fit that every man should bear rule in his own house, and have his wife and children in subjection; rather than that this great rule should be broken, or any encouragement be given to inferior relations to break those bonds asunder, God releases the obligation even of a solemn vow. So much does religion secure the welfare of all societies; and in it the families of the earth have a blessing.